| name | xcode-project-analyzer |
| description | Audit Xcode project configuration, build settings, scheme behavior, and script phases to find build-time improvements with explicit approval gates. Use when a developer wants project-level build analysis, slow incremental builds, guidance on target dependencies, build settings review, run script phase analysis, parallelization improvements, or module-map and DEFINES_MODULE configuration. |
Xcode Project Analyzer
Use this skill for project- and target-level build inefficiencies that are unlikely to be solved by source edits alone.
Core Rules
- Recommendation-first by default.
- Require explicit approval before changing project files, schemes, or build settings.
- Prefer measured findings tied to timing summaries, build logs, or project configuration evidence.
- Distinguish debug-only pain from release-only pain.
What To Review
- scheme build order and target dependencies
- debug vs release build settings against the build settings best practices
- run script phases and dependency-analysis settings
- derived-data churn or obviously invalidating custom steps
- opportunities for parallelization
- explicit module dependency settings and module-map readiness
- "Planning Swift module" time in the Build Timing Summary -- if it dominates incremental builds, suspect unexpected input modification or macro-related invalidation
- asset catalog compilation time, especially in targets with large or numerous catalogs
ExtractAppIntentsMetadata time in the Build Timing Summary -- if this phase consumes significant time, record it as xcode-behavior (report the cost and impact, but do not suggest a repo-local optimization unless there is explicit Apple guidance)
- zero-change build overhead -- if a no-op rebuild exceeds a few seconds, investigate fixed-cost phases (script execution, codesign, validation, CopySwiftLibs)
- CocoaPods usage -- if a
Podfile or Pods.xcodeproj exists, CocoaPods is deprecated; recommend migrating to SPM and do not attempt CocoaPods-specific optimizations (see project-audit-checks.md)
- Task Backtraces (Xcode 16.4+: Scheme Editor > Build > Build Debugging) to diagnose why tasks re-run unexpectedly in incremental builds
Build Settings Best Practices Audit
Every project audit should include a build settings checklist comparing the project's Debug and Release configurations against the recommended values in build-settings-best-practices.md. Present results using checkmark/cross indicators ([x]/[ ]). The scope is strictly build performance -- do not flag language-migration settings like SWIFT_STRICT_CONCURRENCY or SWIFT_UPCOMING_FEATURE_*.
Apple-Derived Checks
Review these items in every audit:
- target dependencies are accurate and not missing or inflated
- schemes build in
Dependency Order
- run scripts declare inputs and outputs
.xcfilelist files are used when scripts have many inputs or outputs
DEFINES_MODULE is enabled where custom frameworks or libraries should expose module maps
- headers are self-contained enough for module-map use
- explicit module dependency settings are consistent for targets that should share modules
Typical Wins
- skip debug-time scripts that only matter in release
- add missing script guards or dependency-analysis metadata
- remove accidental serial bottlenecks in schemes
- align build settings that cause unnecessary module variants
- fix stale project structure that forces broader rebuilds than necessary
- identify linters or formatters that touch file timestamps without changing content, silently invalidating build inputs and forcing module replanning
- split large asset catalogs into separate resource bundles across targets to parallelize compilation
- use Task Backtraces to pinpoint the exact input change that triggers unnecessary incremental work
Reporting Format
For each issue, include:
- evidence
- likely scope
- why it affects clean builds, incremental builds, or both
- estimated impact
- approval requirement
If the evidence points to package graph or build plugins, hand off to spm-build-analysis by reading its SKILL.md and applying its workflow to the same project context.
Additional Resources